Propellek-shaft



'NITED STATES PATENT OFFICE.

A. JOUAN, OF SAN FRANCISCO, CALIFORNIA.

PROPELLER- SHAFT.

Specification of Letters Patent No. 16,091, dated November 18, 1856.

To all whom it may concern.'

Be it known that I, AUGUSTUS JOUAN, of the city of San Francisco, in theState of California, have invented a new and useful Improvement in theConstruction of Steam Propeller- Shafts, and do hereby declare that thefollowing is a full and exact description thereof, reference being hadtothe accompanying drawings and to the letters of reference markedthereon.

The nature of my invention consists in providing for steam propellers ashaft which combines several advantages, among which that of the greatfacility of raising and lowering' the propeller and that of notinterfering with the proper location of the rudder.

To enable others skilled in the art of constructing and navigatingvessels, to make and use my invention, I will proceed to describe mysaid invention.

This shaft is specially intended for steamer propeller shafts It can bemade of any metal but brass should be preferred. It is composed of threeparts (A) (B) (C) united by keys. Its form is conical, about t-he halfof its length circular and the balance triangular as shown by (A). Theupper end of the shaft hangs vertically from the poop of the vessel andthe lower end is connected with a strong metallic stanchion, firmly madeto adhere to the stern post, though the main bearer of the weight of theshaft is the cushion` on which the shaft principally revolves and whichis fixed on the poop, the said stanchion being but an auxiliaryinstrument for the revolution of the shaft and for bearing its weightand is principally intende-d to support the shaft when the vessel isinclined. The conductor of the motor after passing through the sternpost, connects with the shaft at its base.

F or the use of this shaft, the poop of the vessel must be constructedin a way similar as shown in drawing The peculiar form of this shaft iscalculated to suit several purposes; the angular part of it isconvenient to raise the propeller out, and that is done with an ordinarypower; to lower it, the action of its own weight is suflicient, thepropeller goes down and settles where it is intended, producing theextraordinary advantage that by a simple arrangement which can easily becontrived, the propeller can be raised or lowered so as to follow thevariation of the water draft of the vessel and be placed to operate inthe depth most convenient. To that effect nothing is necessary but aconcave angle cut in the central part of the propeller, combining withthe convex angle of the shaft; to facilitate the whole operation theangle of the shaft commences at about two feet above the water line ofthe vessel, when the vessel is in good sailing trim.

From the angular form of the shaft, particularly when it is triangular,among other utilities is resulting that when the vessel is sailingwithout the aid of steam and the propeller is hoisted up, the shaft canbe placed so that one of the angular edges will front the vessel, and inthat way, less resistance will be made to headway. Vitli such acombination of shaft and propeller, the propeller can not become loose,as happens frequently wit-h other arrangements, causing to vessels thenecessity of touching at a port for repair. The location of the rudderon the stern post will be appreciated by navigators.

Very proper remarks have been made in regard to the difficulty ofsteering, consequent to the propeller being placed forward of therudder, causing the water to arrive on the rudder after having lost itssteering power.

I am of opinion that this shaft requires a propeller placed obliquelyand consequently I have applied such a one to my shaft model, not that Ibelieve its form exclusively to be the most advantageous to be used, butto express an impression that I have. It stands about ten degreesobliquely with the shaft, its form when revolving represents an ovalcircle; the blades are of steel, tempered for most elasticity, those areonly painted but should be galvanized, painted and covered with a coatof gutta percha.

)Vhat I claim as my invention and desire to secure by Letters Patent isA propeller shaft, which in its construction is, circular, conical andangular', with these three conditions combined or otherwise, and to beapplied vertically as herein described and shown and for the purposeabove set forth.

A. JOUAN.

Attest W. S. Boss, JOHN S. HOLLINGSHEAD.

